Register for an account

X

Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.

X

Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

Technology

Hot Off the Tress

Researchers use a new microfabrication technique to carve a word into a single human hair.

By Alex StoneOctober 1, 2004 5:00 AM

Newsletter

Sign up for our email newsletter for the latest science news

In a dramatic demonstration of the first-ever method for grafting synthetic materials onto minuscule bits of biological tissue, scientists have stenciled the word hair—in 3-D block letters—on a single human hair. “You can actually make any three-dimensional object you’d like,” says John Fourkas, a chemist at Boston College, who developed the technique along with colleagues at Boston College and Boston University. More important, the technique leaves the underlying tissue unharmed, prefiguring a day when doctors might build miniature sensors directly onto the skin of their patients, or biologists might use microscopic tweezers to capture and study individual cells.

The secret, Fourkas explains, is building the 3-D structures from a special chemical resin, similar to the composite fillings used by dentists, that hardens under low-energy laser light. After bathing the hair in the resin, a computer-guided laser traces out the desired pattern under a microscope, selectively hardening only the areas where the beam strikes. The resin is so sensitive to light, and the beam so tightly focused, that the hair remains intact. “You might imagine that you would end up burning the hair, but this isn’t what happens,” says Fourkas. Furthermore, the laser beam is so precise that it can create parts just a few millionths of an inch wide. Fourkas is now experimenting with ways to fabricate tiny electrical motors or machines using a similar technique.

2 Free Articles Left

Want it all? Get unlimited access when you subscribe.

Subscribe

Already a subscriber? Register or Log In

Want unlimited access?

Subscribe today and save 70%

Subscribe

Already a subscriber? Register or Log In